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1.1 root 1: /*
2: * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
3: *
4: * @APPLE_LICENSE_HEADER_START@
5: *
6: * The contents of this file constitute Original Code as defined in and
7: * are subject to the Apple Public Source License Version 1.1 (the
8: * "License"). You may not use this file except in compliance with the
9: * License. Please obtain a copy of the License at
10: * http://www.apple.com/publicsource and read it before using this file.
11: *
12: * This Original Code and all software distributed under the License are
13: * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
14: * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
15: * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
16: * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
17: * License for the specific language governing rights and limitations
18: * under the License.
19: *
20: * @APPLE_LICENSE_HEADER_END@
21: */
22: /*
23: * Copyright (c) 1982, 1986, 1990, 1993
24: * The Regents of the University of California. All rights reserved.
25: *
26: * Redistribution and use in source and binary forms, with or without
27: * modification, are permitted provided that the following conditions
28: * are met:
29: * 1. Redistributions of source code must retain the above copyright
30: * notice, this list of conditions and the following disclaimer.
31: * 2. Redistributions in binary form must reproduce the above copyright
32: * notice, this list of conditions and the following disclaimer in the
33: * documentation and/or other materials provided with the distribution.
34: * 3. All advertising materials mentioning features or use of this software
35: * must display the following acknowledgement:
36: * This product includes software developed by the University of
37: * California, Berkeley and its contributors.
38: * 4. Neither the name of the University nor the names of its contributors
39: * may be used to endorse or promote products derived from this software
40: * without specific prior written permission.
41: *
42: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
43: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
44: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
45: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
46: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
47: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
48: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
49: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
50: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
51: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52: * SUCH DAMAGE.
53: *
54: * @(#)in.h 8.3 (Berkeley) 1/3/94
55: */
56:
57: #ifndef _NETINET_IN_H_
58: #define _NETINET_IN_H_
59:
60: /*
61: * Constants and structures defined by the internet system,
62: * Per RFC 790, September 1981, and numerous additions.
63: */
64:
65: /*
66: * Protocols (RFC 1700)
67: */
68: #define IPPROTO_IP 0 /* dummy for IP */
69: #define IPPROTO_ICMP 1 /* control message protocol */
70: #define IPPROTO_IGMP 2 /* group mgmt protocol */
71: #define IPPROTO_GGP 3 /* gateway^2 (deprecated) */
72: #define IPPROTO_IPIP 4 /* IP encapsulation in IP */
73: #define IPPROTO_TCP 6 /* tcp */
74: #define IPPROTO_ST 7 /* Stream protocol II */
75: #define IPPROTO_EGP 8 /* exterior gateway protocol */
76: #define IPPROTO_PIGP 9 /* private interior gateway */
77: #define IPPROTO_RCCMON 10 /* BBN RCC Monitoring */
78: #define IPPROTO_NVPII 11 /* network voice protocol*/
79: #define IPPROTO_PUP 12 /* pup */
80: #define IPPROTO_ARGUS 13 /* Argus */
81: #define IPPROTO_EMCON 14 /* EMCON */
82: #define IPPROTO_XNET 15 /* Cross Net Debugger */
83: #define IPPROTO_CHAOS 16 /* Chaos*/
84: #define IPPROTO_UDP 17 /* user datagram protocol */
85: #define IPPROTO_MUX 18 /* Multiplexing */
86: #define IPPROTO_MEAS 19 /* DCN Measurement Subsystems */
87: #define IPPROTO_HMP 20 /* Host Monitoring */
88: #define IPPROTO_PRM 21 /* Packet Radio Measurement */
89: #define IPPROTO_IDP 22 /* xns idp */
90: #define IPPROTO_TRUNK1 23 /* Trunk-1 */
91: #define IPPROTO_TRUNK2 24 /* Trunk-2 */
92: #define IPPROTO_LEAF1 25 /* Leaf-1 */
93: #define IPPROTO_LEAF2 26 /* Leaf-2 */
94: #define IPPROTO_RDP 27 /* Reliable Data */
95: #define IPPROTO_IRTP 28 /* Reliable Transaction */
96: #define IPPROTO_TP 29 /* tp-4 w/ class negotiation */
97: #define IPPROTO_BLT 30 /* Bulk Data Transfer */
98: #define IPPROTO_NSP 31 /* Network Services */
99: #define IPPROTO_INP 32 /* Merit Internodal */
100: #define IPPROTO_SEP 33 /* Sequential Exchange */
101: #define IPPROTO_3PC 34 /* Third Party Connect */
102: #define IPPROTO_IDPR 35 /* InterDomain Policy Routing */
103: #define IPPROTO_XTP 36 /* XTP */
104: #define IPPROTO_DDP 37 /* Datagram Delivery */
105: #define IPPROTO_CMTP 38 /* Control Message Transport */
106: #define IPPROTO_TPXX 39 /* TP++ Transport */
107: #define IPPROTO_IL 40 /* IL transport protocol */
108: #define IPPROTO_SIP 41 /* Simple Internet Protocol */
109: #define IPPROTO_SDRP 42 /* Source Demand Routing */
110: #define IPPROTO_SIPSR 43 /* SIP Source Route */
111: #define IPPROTO_SIPFRAG 44 /* SIP Fragment */
112: #define IPPROTO_IDRP 45 /* InterDomain Routing*/
113: #define IPPROTO_RSVP 46 /* resource reservation */
114: #define IPPROTO_GRE 47 /* General Routing Encap. */
115: #define IPPROTO_MHRP 48 /* Mobile Host Routing */
116: #define IPPROTO_BHA 49 /* BHA */
117: #define IPPROTO_ESP 50 /* SIPP Encap Sec. Payload */
118: #define IPPROTO_AH 51 /* SIPP Auth Header */
119: #define IPPROTO_INLSP 52 /* Integ. Net Layer Security */
120: #define IPPROTO_SWIPE 53 /* IP with encryption */
121: #define IPPROTO_NHRP 54 /* Next Hop Resolution */
122: /* 55-60: Unassigned */
123: #define IPPROTO_AHIP 61 /* any host internal protocol */
124: #define IPPROTO_CFTP 62 /* CFTP */
125: #define IPPROTO_HELLO 63 /* "hello" routing protocol */
126: #define IPPROTO_SATEXPAK 64 /* SATNET/Backroom EXPAK */
127: #define IPPROTO_KRYPTOLAN 65 /* Kryptolan */
128: #define IPPROTO_RVD 66 /* Remote Virtual Disk */
129: #define IPPROTO_IPPC 67 /* Pluribus Packet Core */
130: #define IPPROTO_ADFS 68 /* Any distributed FS */
131: #define IPPROTO_SATMON 69 /* Satnet Monitoring */
132: #define IPPROTO_VISA 70 /* VISA Protocol */
133: #define IPPROTO_IPCV 71 /* Packet Core Utility */
134: #define IPPROTO_CPNX 72 /* Comp. Prot. Net. Executive */
135: #define IPPROTO_CPHB 73 /* Comp. Prot. HeartBeat */
136: #define IPPROTO_WSN 74 /* Wang Span Network */
137: #define IPPROTO_PVP 75 /* Packet Video Protocol */
138: #define IPPROTO_BRSATMON 76 /* BackRoom SATNET Monitoring */
139: #define IPPROTO_ND 77 /* Sun net disk proto (temp.) */
140: #define IPPROTO_WBMON 78 /* WIDEBAND Monitoring */
141: #define IPPROTO_WBEXPAK 79 /* WIDEBAND EXPAK */
142: #define IPPROTO_EON 80 /* ISO cnlp */
143: #define IPPROTO_VMTP 81 /* VMTP */
144: #define IPPROTO_SVMTP 82 /* Secure VMTP */
145: #define IPPROTO_VINES 83 /* Banyon VINES */
146: #define IPPROTO_TTP 84 /* TTP */
147: #define IPPROTO_IGP 85 /* NSFNET-IGP */
148: #define IPPROTO_DGP 86 /* dissimilar gateway prot. */
149: #define IPPROTO_TCF 87 /* TCF */
150: #define IPPROTO_IGRP 88 /* Cisco/GXS IGRP */
151: #define IPPROTO_OSPFIGP 89 /* OSPFIGP */
152: #define IPPROTO_SRPC 90 /* Strite RPC protocol */
153: #define IPPROTO_LARP 91 /* Locus Address Resoloution */
154: #define IPPROTO_MTP 92 /* Multicast Transport */
155: #define IPPROTO_AX25 93 /* AX.25 Frames */
156: #define IPPROTO_IPEIP 94 /* IP encapsulated in IP */
157: #define IPPROTO_MICP 95 /* Mobile Int.ing control */
158: #define IPPROTO_SCCSP 96 /* Semaphore Comm. security */
159: #define IPPROTO_ETHERIP 97 /* Ethernet IP encapsulation */
160: #define IPPROTO_ENCAP 98 /* encapsulation header */
161: #define IPPROTO_APES 99 /* any private encr. scheme */
162: #define IPPROTO_GMTP 100 /* GMTP*/
163: /* 101-254: Unassigned */
164: /* 255: Reserved */
165: /* BSD Private, local use, namespace incursion */
166: #define IPPROTO_DIVERT 254 /* divert pseudo-protocol */
167: #define IPPROTO_RAW 255 /* raw IP packet */
168: #define IPPROTO_MAX 256
169:
170:
171: /*
172: * Local port number conventions:
173: *
174: * When a user does a bind(2) or connect(2) with a port number of zero,
175: * a non-conflicting local port address is chosen.
176: * The default range is IPPORT_RESERVED through
177: * IPPORT_USERRESERVED, although that is settable by sysctl.
178: *
179: * A user may set the IPPROTO_IP option IP_PORTRANGE to change this
180: * default assignment range.
181: *
182: * The value IP_PORTRANGE_DEFAULT causes the default behavior.
183: *
184: * The value IP_PORTRANGE_HIGH changes the range of candidate port numbers
185: * into the "high" range. These are reserved for client outbound connections
186: * which do not want to be filtered by any firewalls.
187: *
188: * The value IP_PORTRANGE_LOW changes the range to the "low" are
189: * that is (by convention) restricted to privileged processes. This
190: * convention is based on "vouchsafe" principles only. It is only secure
191: * if you trust the remote host to restrict these ports.
192: *
193: * The default range of ports and the high range can be changed by
194: * sysctl(3). (net.inet.ip.port{hi,low}{first,last}_auto)
195: *
196: * Changing those values has bad security implications if you are
197: * using a a stateless firewall that is allowing packets outside of that
198: * range in order to allow transparent outgoing connections.
199: *
200: * Such a firewall configuration will generally depend on the use of these
201: * default values. If you change them, you may find your Security
202: * Administrator looking for you with a heavy object.
203: *
204: * For a slightly more orthodox text view on this:
205: *
206: * ftp://ftp.isi.edu/in-notes/iana/assignments/port-numbers
207: *
208: * port numbers are divided into three ranges:
209: *
210: * 0 - 1023 Well Known Ports
211: * 1024 - 49151 Registered Ports
212: * 49152 - 65535 Dynamic and/or Private Ports
213: *
214: */
215:
216: /*
217: * Ports < IPPORT_RESERVED are reserved for
218: * privileged processes (e.g. root). (IP_PORTRANGE_LOW)
219: * Ports > IPPORT_USERRESERVED are reserved
220: * for servers, not necessarily privileged. (IP_PORTRANGE_DEFAULT)
221: */
222: #define IPPORT_RESERVED 1024
223: #define IPPORT_USERRESERVED 5000
224:
225: /*
226: * Default local port range to use by setting IP_PORTRANGE_HIGH
227: */
228: #define IPPORT_HIFIRSTAUTO 49152
229: #define IPPORT_HILASTAUTO 65535
230:
231: /*
232: * Scanning for a free reserved port return a value below IPPORT_RESERVED,
233: * but higher than IPPORT_RESERVEDSTART. Traditionally the start value was
234: * 512, but that conflicts with some well-known-services that firewalls may
235: * have a fit if we use.
236: */
237: #define IPPORT_RESERVEDSTART 600
238:
239: /*
240: * Internet address (a structure for historical reasons)
241: */
242: struct in_addr {
243: u_int32_t s_addr;
244: };
245:
246: /*
247: * Definitions of bits in internet address integers.
248: * On subnets, the decomposition of addresses to host and net parts
249: * is done according to subnet mask, not the masks here.
250: */
251: #define IN_CLASSA(i) (((u_int32_t)(i) & 0x80000000) == 0)
252: #define IN_CLASSA_NET 0xff000000
253: #define IN_CLASSA_NSHIFT 24
254: #define IN_CLASSA_HOST 0x00ffffff
255: #define IN_CLASSA_MAX 128
256:
257: #define IN_CLASSB(i) (((u_int32_t)(i) & 0xc0000000) == 0x80000000)
258: #define IN_CLASSB_NET 0xffff0000
259: #define IN_CLASSB_NSHIFT 16
260: #define IN_CLASSB_HOST 0x0000ffff
261: #define IN_CLASSB_MAX 65536
262:
263: #define IN_CLASSC(i) (((u_int32_t)(i) & 0xe0000000) == 0xc0000000)
264: #define IN_CLASSC_NET 0xffffff00
265: #define IN_CLASSC_NSHIFT 8
266: #define IN_CLASSC_HOST 0x000000ff
267:
268: #define IN_CLASSD(i) (((u_int32_t)(i) & 0xf0000000) == 0xe0000000)
269: #define IN_CLASSD_NET 0xf0000000 /* These ones aren't really */
270: #define IN_CLASSD_NSHIFT 28 /* net and host fields, but */
271: #define IN_CLASSD_HOST 0x0fffffff /* routing needn't know. */
272: #define IN_MULTICAST(i) IN_CLASSD(i)
273:
274: #define IN_EXPERIMENTAL(i) (((u_int32_t)(i) & 0xf0000000) == 0xf0000000)
275: #define IN_BADCLASS(i) (((u_int32_t)(i) & 0xf0000000) == 0xf0000000)
276:
277: #define INADDR_ANY (u_int32_t)0x00000000
278: #define INADDR_LOOPBACK (u_int32_t)0x7f000001
279: #define INADDR_BROADCAST (u_int32_t)0xffffffff /* must be masked */
280: #ifndef KERNEL
281: #define INADDR_NONE 0xffffffff /* -1 return */
282: #endif
283:
284: #define INADDR_UNSPEC_GROUP (u_int32_t)0xe0000000 /* 224.0.0.0 */
285: #define INADDR_ALLHOSTS_GROUP (u_int32_t)0xe0000001 /* 224.0.0.1 */
286: #define INADDR_ALLRTRS_GROUP (u_int32_t)0xe0000002 /* 224.0.0.2 */
287: #define INADDR_MAX_LOCAL_GROUP (u_int32_t)0xe00000ff /* 224.0.0.255 */
288:
289: #define IN_LOOPBACKNET 127 /* official! */
290:
291: /*
292: * Socket address, internet style.
293: */
294: struct sockaddr_in {
295: u_char sin_len;
296: u_char sin_family;
297: u_short sin_port;
298: struct in_addr sin_addr;
299: char sin_zero[8];
300: };
301:
302: /*
303: * Structure used to describe IP options.
304: * Used to store options internally, to pass them to a process,
305: * or to restore options retrieved earlier.
306: * The ip_dst is used for the first-hop gateway when using a source route
307: * (this gets put into the header proper).
308: */
309: struct ip_opts {
310: struct in_addr ip_dst; /* first hop, 0 w/o src rt */
311: char ip_opts[40]; /* actually variable in size */
312: };
313:
314: /*
315: * Options for use with [gs]etsockopt at the IP level.
316: * First word of comment is data type; bool is stored in int.
317: */
318: #define IP_OPTIONS 1 /* buf/ip_opts; set/get IP options */
319: #define IP_HDRINCL 2 /* int; header is included with data */
320: #define IP_TOS 3 /* int; IP type of service and preced. */
321: #define IP_TTL 4 /* int; IP time to live */
322: #define IP_RECVOPTS 5 /* bool; receive all IP opts w/dgram */
323: #define IP_RECVRETOPTS 6 /* bool; receive IP opts for response */
324: #define IP_RECVDSTADDR 7 /* bool; receive IP dst addr w/dgram */
325: #define IP_RETOPTS 8 /* ip_opts; set/get IP options */
326: #define IP_MULTICAST_IF 9 /* u_char; set/get IP multicast i/f */
327: #define IP_MULTICAST_TTL 10 /* u_char; set/get IP multicast ttl */
328: #define IP_MULTICAST_LOOP 11 /* u_char; set/get IP multicast loopback */
329: #define IP_ADD_MEMBERSHIP 12 /* ip_mreq; add an IP group membership */
330: #define IP_DROP_MEMBERSHIP 13 /* ip_mreq; drop an IP group membership */
331: #define IP_MULTICAST_VIF 14 /* set/get IP mcast virt. iface */
332: #define IP_RSVP_ON 15 /* enable RSVP in kernel */
333: #define IP_RSVP_OFF 16 /* disable RSVP in kernel */
334: #define IP_RSVP_VIF_ON 17 /* set RSVP per-vif socket */
335: #define IP_RSVP_VIF_OFF 18 /* unset RSVP per-vif socket */
336: #define IP_PORTRANGE 19 /* int; range to choose for unspec port */
337: #define IP_RECVIF 20 /* bool; receive reception if w/dgram */
338: #define IP_STRIPHDR 21 /* bool: drop receive of raw IP header */
339:
340: #define IP_FW_ADD 50 /* add a firewall rule to chain */
341: #define IP_FW_DEL 51 /* delete a firewall rule from chain */
342: #define IP_FW_FLUSH 52 /* flush firewall rule chain */
343: #define IP_FW_ZERO 53 /* clear single/all firewall counter(s) */
344: #define IP_FW_GET 54 /* get entire firewall rule chain */
345: #define IP_NAT 55 /* set/get NAT opts */
346:
347: #define IP_DUMMYNET_CONFIGURE 60 /* add/configure a dummynet pipe */
348: #define IP_DUMMYNET_DEL 61 /* delete a dummynet pipe from chain */
349: #define IP_DUMMYNET_FLUSH 62 /* flush dummynet */
350: #define IP_DUMMYNET_GET 64 /* get entire dummynet pipes */
351:
352: /*
353: * Defaults and limits for options
354: */
355: #define IP_DEFAULT_MULTICAST_TTL 1 /* normally limit m'casts to 1 hop */
356: #define IP_DEFAULT_MULTICAST_LOOP 1 /* normally hear sends if a member */
357: #define IP_MAX_MEMBERSHIPS 20 /* per socket */
358:
359: /*
360: * Argument structure for IP_ADD_MEMBERSHIP and IP_DROP_MEMBERSHIP.
361: */
362: struct ip_mreq {
363: struct in_addr imr_multiaddr; /* IP multicast address of group */
364: struct in_addr imr_interface; /* local IP address of interface */
365: };
366:
367: /*
368: * Argument for IP_PORTRANGE:
369: * - which range to search when port is unspecified at bind() or connect()
370: */
371: #define IP_PORTRANGE_DEFAULT 0 /* default range */
372: #define IP_PORTRANGE_HIGH 1 /* "high" - request firewall bypass */
373: #define IP_PORTRANGE_LOW 2 /* "low" - vouchsafe security */
374:
375: /*
376: * Definitions for inet sysctl operations.
377: *
378: * Third level is protocol number.
379: * Fourth level is desired variable within that protocol.
380: */
381: #define IPPROTO_MAXID (IPPROTO_IDP + 1) /* don't list to IPPROTO_MAX */
382:
383: #define CTL_IPPROTO_NAMES { \
384: { "ip", CTLTYPE_NODE }, \
385: { "icmp", CTLTYPE_NODE }, \
386: { "igmp", CTLTYPE_NODE }, \
387: { "ggp", CTLTYPE_NODE }, \
388: { 0, 0 }, \
389: { 0, 0 }, \
390: { "tcp", CTLTYPE_NODE }, \
391: { 0, 0 }, \
392: { "egp", CTLTYPE_NODE }, \
393: { 0, 0 }, \
394: { 0, 0 }, \
395: { 0, 0 }, \
396: { "pup", CTLTYPE_NODE }, \
397: { 0, 0 }, \
398: { 0, 0 }, \
399: { 0, 0 }, \
400: { 0, 0 }, \
401: { "udp", CTLTYPE_NODE }, \
402: { 0, 0 }, \
403: { 0, 0 }, \
404: { 0, 0 }, \
405: { 0, 0 }, \
406: { "idp", CTLTYPE_NODE }, \
407: }
408:
409: /*
410: * Names for IP sysctl objects
411: */
412: #define IPCTL_FORWARDING 1 /* act as router */
413: #define IPCTL_SENDREDIRECTS 2 /* may send redirects when forwarding */
414: #define IPCTL_DEFTTL 3 /* default TTL */
415: #ifdef notyet
416: #define IPCTL_DEFMTU 4 /* default MTU */
417: #endif
418: #define IPCTL_RTEXPIRE 5 /* cloned route expiration time */
419: #define IPCTL_RTMINEXPIRE 6 /* min value for expiration time */
420: #define IPCTL_RTMAXCACHE 7 /* trigger level for dynamic expire */
421: #define IPCTL_SOURCEROUTE 8 /* may perform source routes */
422: #define IPCTL_DIRECTEDBROADCAST 9 /* may re-broadcast received packets */
423: #define IPCTL_INTRQMAXLEN 10 /* max length of netisr queue */
424: #define IPCTL_INTRQDROPS 11 /* number of netisr q drops */
425: #define IPCTL_STATS 12 /* ipstat structure */
426: #define IPCTL_ACCEPTSOURCEROUTE 13 /* may accept source routed packets */
427: #define IPCTL_FASTFORWARDING 14 /* use fast IP forwarding code */
428: #define IPCTL_MAXID 15
429:
430: #define IPCTL_NAMES { \
431: { 0, 0 }, \
432: { "forwarding", CTLTYPE_INT }, \
433: { "redirect", CTLTYPE_INT }, \
434: { "ttl", CTLTYPE_INT }, \
435: { "mtu", CTLTYPE_INT }, \
436: { "rtexpire", CTLTYPE_INT }, \
437: { "rtminexpire", CTLTYPE_INT }, \
438: { "rtmaxcache", CTLTYPE_INT }, \
439: { "sourceroute", CTLTYPE_INT }, \
440: { "directed-broadcast", CTLTYPE_INT }, \
441: { "intr-queue-maxlen", CTLTYPE_INT }, \
442: { "intr-queue-drops", CTLTYPE_INT }, \
443: { "stats", CTLTYPE_STRUCT }, \
444: { "accept_sourceroute", CTLTYPE_INT }, \
445: { "fastforwarding", CTLTYPE_INT }, \
446: }
447:
448:
449: #ifdef KERNEL
450: struct ifnet; struct mbuf; /* forward declarations for Standard C */
451:
452: int in_broadcast __P((struct in_addr, struct ifnet *));
453: int in_canforward __P((struct in_addr));
454: int in_cksum __P((struct mbuf *, int));
455: int in_localaddr __P((struct in_addr));
456: char *inet_ntoa __P((struct in_addr)); /* in libkern */
457:
458: #endif /* KERNEL */
459:
460: #endif
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